Self-powered rfid sensing system for structural health monitoring

Abstract

An RFID-based sensing system includes a piezoelectric arrangement mountable at least partially on a structure, an RFID transponder connected to the piezoelectric arrangement, and an antenna connected to the RFID transponder and/or being integrated into the RFID transponder. The piezoelectric arrangement and/or the RFID transponder are adapted to convert kinetic energy provided by the structure into electrical energy usable for powering the RFID transponder and to generate sensing information with respect to a state of the structure. The RFID-based sensing system also includes an RFID reader.

1 - 22 . (canceled) 
     
     
         23 . An RFID-based sensing system comprising:
 a piezoelectric arrangement adapted to be mountable and/or being mounted at least partially on a structure;   an RFID transponder adapted to be connected and/or being connected to the piezoelectric arrangement; and   an antenna adapted to be connected and/or being connected to the RFID transponder and/or being integrated into the RFID transponder;   wherein at least one of the piezoelectric arrangement and the RFID transponder is adapted to convert kinetic energy provided by the structure into electrical energy used and/or usable for powering at least one of the RFID transponder and the antenna and to generate sensing information with respect to a state of the structure, and   wherein the antenna is adapted to transmit the sensing information and/or information derived therefrom to an RFID reader and/or to receive an RF signal from the reader.   
     
     
         24 . An RFID-based sensing system according to  claim 23 , wherein the piezoelectric arrangement comprises at least one piezoelectric element, and wherein at least one of the piezoelectric element(s) is/are adapted to be mounted and/or mounted on the structure and adapted to be connected and/or connected to the RFID transponder. 
     
     
         25 . An RFID-based sensing system according  claim 24 , wherein the piezoelectric arrangement comprises at least one piezoelectric converting and sensing element being adapted, to convert kinetic energy provided by the structure into electrical energy used and/or usable for powering the RFID transponder, and to generate sensing information with respect to a state of the structure. 
     
     
         26 . An RFID-based sensing system according to  claim 24 , wherein the piezoelectric arrangement comprises:
 at least one piezoelectric converting element being adapted to convert kinetic energy provided by the structure into electrical energy used and/or usable for powering the RFID transponder; and   at least one piezoelectric sensing element being adapted to generate sensing information with respect to a state of the structure.   
     
     
         27 . An RFID-based sensing system according to  claim 23 , wherein at least one of the RFID transponder and the piezoelectric arrangement is adapted to alternately switch between a first state in which kinetic energy provided by the structure is converted into electrical energy used and/or usable for powering the RFID transponder and a second state in which sensing information with respect to a state of the structure is generated. 
     
     
         28 . An RFID-based sensing system according to  claim 23 , wherein at least one of the RFID transponder and the piezoelectric arrangement comprises a sensor interface adapted to sample a signal resulting from at least one piezoelectric sensing element and/or piezoelectric converting and sensing element, to measure a voltage output generated by at least one piezoelectric sensing element and/or piezoelectric converting and sensing element and/or to measure a variation of the electrical impedance of one piezoelectric sensing element and/or piezoelectric converting and sensing element. 
     
     
         29 . An RFID-based sensing system according to  claim 28 , wherein the sensor interface is further adapted to also generate the sensing information with respect to a state of the structure. 
     
     
         30 . An RFID-based sensing system according to  claim 28 , wherein the sensor interface is adapted to digitize and/or to modify the resulting signal, the voltage output and/or the variation of the electrical impedance by amplification, attenuation or low-pass filtering or by offset-change of the signal's DC value. 
     
     
         31 . An RFID-based sensing system according to  claim 30 , wherein at least one of the RFID transponder and the piezoelectric arrangement comprises)a memory, and wherein the sensor interface is adapted to store information associated with a state of the structure and/or identification information with respect to the RFID transponder and/or at least one piezoelectric element of the piezoelectric arrangement in the memory. 
     
     
         32 . An RFID-based sensing system according to one  claim 23 , wherein at least one of the RFID transponder and the piezoelectric arrangement comprises an energy storage, the energy storage being adapted to store at least part of the electrical energy gained by conversion of the kinetic energy and adapted to power the RFID transponder. 
     
     
         33 . An RFID-based sensing system according to  claim 23 , wherein the RFID transponder is connected to an energy storage. 
     
     
         34 . An RFID-based sensing system according  claim 32 , further comprising a rectifier connected between the piezoelectric arrangement and the energy storage. 
     
     
         35 . An RFID-based sensing system according to  claim 32 , wherein at least one of the RFID transponder and the piezoelectric arrangement is adapted to alternately switch between a first state, in which kinetic energy provided by the structure is converted into electrical energy and stored in the energy storage and in which no sensing information with respect to a state of the structure is generated, and a second state, in which sensing information with respect to a state of the structure is generated, but no energy is stored in the energy storage. 
     
     
         36 . An RFID-based sensing system according to  claim 23 , wherein at least one of the RFID transponder and the piezoelectric arrangement comprises a power management circuit adapted to generate a power down signal that is able to set at least part of the RFID-based sensing system in a low-power operation mode in which only a restricted number of predefined functionalities is available. 
     
     
         37 . An RFID-based sensing system according to  claim 23 , wherein the RFID transponder comprises, at an input terminal connected to the piezoelectric arrangement, a voltage limiter adapted to provide a low impedance path for input voltages higher than a predefined voltage threshold. 
     
     
         38 . An RFID-based sensing system according to  claim 23 , wherein at least one of the RFID transponder and the piezoelectric arrangement comprises a voltage regulator adapted to provide a stable, temperature independent voltage supply for the RFID-based sensing system. 
     
     
         39 . An RFID-based sensing system according to  claim 23 , wherein the RFID transponder comprises, at an output terminal connected to the antenna, an envelope detector adapted to determine an envelope shape of an amplitude modulated RF signal received by the antenna. 
     
     
         40 . An RFID-based sensing system according to  claim 39 , wherein the RFID transponder comprises, connected to the envelope detector, a demodulator adapted to provide a base-band signal extracted from the envelope of an amplitude modulated RF signal received by the antenna. 
     
     
         41 . An RFID-based sensing system according to  claim 40 , wherein the RFID transponder comprises, at an output terminal connected to the antenna, a modulator adapted to generate, from the sensing information and/or the information derived therefrom, a modulated signal to be transmitted by the antenna. 
     
     
         42 . An RFID-based sensing system according to  claim 40 , wherein at least one of the RFID transponder and the piezoelectric arrangement comprises a main control logic circuit connected to the sensor interface, the memory, the demodulator and the modulator, the main control logic circuit being adapted to control the functionalities of the RFID-based sensing system. 
     
     
         43 . An RFID-based sensing system according  claim 42 , wherein the RFID transponder comprises one integrated RFID chip to which the antenna is connected as an external antenna. 
     
     
         44 . An RFID-based sensing system according  claim 43 , wherein the RFID chip comprises the sensor interface, the memory, the rectifier, the power management circuit, the voltage limiter, the voltage regulator, the envelope detector, the demodulator, the modulator and the main control logic circuit. 
     
     
         45 . An RFID-based sensing system according to  claim 23 , wherein the RFID transponder comprises one of:
 an active RFID transponder in which energy consumed by the RFID transponder can be provided by an external energy source;   a semi-passive RFID transponder in which energy consumed by the RFID transponder can be provided by at least one of the piezoelectric arrangement and the electromagnetic field radiated by an RFID-based reader; or   a passive RFID transponder in which energy consumed by the RFID transponder can be provided by at least one of the piezoelectric arrangement and the electromagnetic field radiated by an RFID-based reader.   
     
     
         46 . An RFID-based sensing system according to  claim 23 , wherein the structure comprises one of a bridge, a building, a dam, a pipeline, a windmill, an aircraft, a car, a train or a ship. 
     
     
         47 . An RFID-based sensing and reading system comprising:
 at least one RFID-based sensing system, the at least one RFID-based sensing system including:
 a piezoelectric arrangement mountable at least partially on a structure; 
 an RFID transponder connectable to the piezoelectric arrangement; and 
 an antenna connectable to or integrated with the RFID transponder; 
 at least one of the piezoelectric arrangement and the RFID transponder being adapted to convert kinetic energy provided by the structure into electrical energy used and/or usable for powering at least one of the RFID transponder and the antenna and to generate sensing information with respect to a state of the structure, and 
   at least one RFID based reader comprising a further antenna and being adapted to receive sensing information and/or information derived therefrom from the at least one RFID based sensing system and/or to transmit an RF signal to the at least one RFID based sensing system.   
     
     
         48 . An RFID-based sensing and reading system according to  claim 47 , wherein the system includes multiple RFID-based sensing systems and exactly one RFID-based reader. 
     
     
         49 . An RFID-based sensing and reading system according to  claim 47 , wherein at least one of the RFID-based sensing systems comprise a piezoelectric arrangement with multiple piezoelectric elements adapted to be mounted on or integrated in and/or being mounted on or integrated in a structure, and wherein at least one of the RFID-based readers is adapted to read sensing information and/or information derived therefrom from the multiple piezoelectric elements. 
     
     
         50 . An RFID-based transmitting and receiving method in which a piezoelectric arrangement is mounted at least partially on a structure, an RFID transponder is connected to the piezoelectric arrangement, and an antenna is connected to the RFID transponder and/or integrated into the RFID transponder, the method comprising:
 converting, via the piezoelectric arrangement and/or the RFID transponder, kinetic energy provided by the structure into electrical energy;   using the electrical energy to power the RFID transponder and to generate sensing information with respect to a state of the structure;   transmitting, via the antenna, the sending information and/or information derived therefrom, to an RFID reader; and   receiving the transmitted information via the RFID reader.